Swivel



C. S. BAKER SWIVEL Filed Oct. 2, 1923 Patented Jan. 13, 1925.

CALVIN S. BAKER, 0F PORTLAND, OREGON.

SWIVEL.

Application filed October 2, 1923., Serial No. 666,140.

To all whom it may concern:

Be it known that I, CALVIN S. BAKER, a citizen ofthe United States, residing at Portland, county of Multnomah, State of Oregon, have invented certain new and useful Improvements in Swivels, of which the following is a specification.

My invention relates to swivels in general, and particularly to swivels insertable in electric extensions such as are used for drop lights, electric irons and like devices, the object being to provide a swivel that will render twisting of the extension wires impossible'while at the same timenot interfering with the passage of the electric current.

I accomplish the above object by means of the construction illustrated in the accompanying drawing, which is a part of this application for letters patent, like characters of reference indicating like parts throughout the several views thereof, and in which:

Fig. 1 is a sectional elevation of my device; Figs. 2, 3 and 4 are sections upon their respective lines of Fig. 1; Figs. 5, 6, 7 and 8 are detail views of the pivotally mounted electric contacts in various positions, drawn to an enlarged scale; Fig. 9 is a perspective detail of one of the collector rings; Fig. 10 is a detail perspective view of the smaller collector ring contact; Figs. 11 and 12 are perspective details respectively of the brackets for the pivotally mounted contacts.

In general my device consists of acircular casing composed of a body and a cap rotatively secured together, one of said casing parts bearing electrical collector rings and the other bearing pivotally mounted contacts coat-ting respectively with said rings, said rings and said contacts being connected in series with the wires of an ordinary twisted electric cord.

The casing is composed of a body 13 having a centrally disposed hub 14, upon which hub is rotatably mounted a cap 15 by the convenient means of the washer 16 and screw 17. Upon the casing body 13 is secured a collector ring 18, conveniently provided with an annular groove upon its exposed face for the reception of coacting contacts, and having a projecting contact 19 to which one of the electric wires-20, projecting through an orifice in the body 13, is attached. Upon the hub 14 is secured a smaller collector ring 21 concentrate with the former mentioned collector ring 18, and conveniently provided with an annular groove upon the lower face thereof to coact with an electric contact. An angle contact member 22 is provided, and is embedded into the hub 14 and also into the body 13, and serves to electrically connect the collector ring 21 with the electric wire 23 which projects through an orifice in the body 13 and is attached to the contact member 22.

Mounted upon the cap '15 are brackets 24 and 25, which are connected respectively to wires 26 and 27 which project through orifices in the cap 15. Upon bracket 24 is pivotally mounted a contact 28. and upon bracket 25 is pivotally'mounted a contact 29. Said contacts are respectively curved to fit the curvature of their collector rings; that is contact 28 is curved to a radius R equal to the radius R of the collector ring 21. and contact 29 is curved to a radius R equal to the radius R of the collector ring 18. As the cap 15 and body 13 of the casing rotate relatively the contacts 28 and 29 ride within the grooves in their respec tive collector rings 21 and 18.

To provide that said contacts shall always be in contact with their respective collector rings irrespective of the position of the casing I construct said contacts in a novel manner as follows. The periphery of each contact is composed of a circular arc portion 30 and two oppositely projecting tangential portions 31 and 32. The radius of the circular arc portions being such that the contacts will contact with the surfaces of the collector ring grooves, as shown in Figs. 5 and 6. The tangential portions 32 are made longer than the tangential portions 31 so that the contacts are out of bal- -ance upon their pivotal mounting points.

When the device is in the position shown in Fig. 1, the contacts 28 and 29 will assume the position shown in Fig. 7. the longer tangential portion 32 outbalancing the shorter tangential portion 31 and causing the contact to rotate upon its pivot until stopped by the contact of the short tangential portion 31 with the collector ring. When the device is reversed from the position shown in.Fig. 1, the contacts will assume the. position shown in Fig. 8, the longer tangential portion outbalancing the shorter tangential portion and causing the contact to rotate upon its pivotal mounting point until stopped by the contact of the longer tangential portion with the collector ring. It is obvious that as the casing is inclined to one side or the other the contacts ".58 and 29 will thus rotate upon their respective pivots, and thus remain in contact with their respective collector rings irrespective of whether the casing is in a vertical position as shown in Fig. 1 or the reverse thereof.

My device may be made of any size, and constructed of any materials deemed convenient and suitable for a device of this character, and while I have illustrated and described a form of construction and arrangement of parts found desirable in materializing my invention, I wish to include in this application all mechanical equivalents and substitutes that may fairly be considered to come within the scope and pur- View of my invention as defined in the appendedclaims. 7

Having disclosed my invention so that others may be enabled to construct and to use the same, what I claim as new, and de- Sire to secure by Letters Patent is:

1. In a swivel; a body; a cap rotatably mounted upon said body; a pair of collectorrings mounted upon saidbody; a pair of contacts pivotally mounted u on said ca and coacting respectively wit said co ector rings, said contacts being out of balance upon their respective pivots for the purpose of keeping portions of said contacts always in contact with their respective collector rings.

2. In a swivel; a pair of relatively rotatable connected members; contacts pivotally mounted in an out of balance position upon one of said members; and, collector rings upon the other of said members coacting respectively with said contacts.

3. In a swivel: a casing composed of a body, a hub upon said body, and a cap rotatably mounted upon said hub; a collector ring upon said body; a collector ring upon said hub; a pair of brackets upon said cap adjacent respectively to said collector rings: and contacts pivotally mounted in said brackets in an out of balance position and ooacting respectively with said collector rings.

In witness whereof I claim the foregoing as my own I hereunto afiix my signature in the presence of two witnesses at Portland, county of Multnomah, State of Oregon, this 10th day of Jan. 1923.

CALVIN S. BAKER.

Witnesses:

L; J. RoBmsoN. C. F. BLAKE. 

